Post by zuthal on Dec 25, 2017 9:53:37 GMT

I had the idea that it might be possible to simulate the coolant changing phase (and thus taking a lot more heat away than it normally would) by altering the melting point and the heat capacity of the coolant to simulate the full heat absorbed during the phase change.

For example, aluminium boils at an acceptable pressure for use in our reactors, and has a heat of vaporisation of about 10800 kJ/kg. By increasing the melting point to 2300 K and the specific heat by 108 kJ/kg*K, we can simulate this for the outer coolant loop of a reactor with a 2400 K exit temperature.

The reactor with boiling metal coolant is, for the same power output, about 33% lighter and shorter than the conventionally cooled one.

This should allow much lower pump speeds, and thus lighter reactors. The downside is that you must create a new material for each temperature differential (for the inner coolant loop) or for each coolant exit temperature (for the outer coolant loop, as there the coolant returns at the melting point) in order for it to work.